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Hi i have a 1988 omc 2.3l cobr

Hi i have a 1988 omc 2.3l cobra 1750 bayliner.
I am looking for advice on how to set my carb on the boat.
It has 2 screws i think 1 is for choke and the other is for idle it burns a light grey smoke on start up and smells heavily of petrol when its warm it seems ok but it seems to run to rich what are the settings how do you adjust it help

"Im no expert here but, mabey

"Im no expert here but, mabey I can help. What I did was start the engine and let it warm up to operating temp. set the idle speed to spec &#40; i set mine around 650-700&#41;. Then adjust the mixture.The idea is to get the mixture set as lean as possible, but not to where the RPM is dropping off a lot, and without affecting engine performance. This will usually be just as the RPM begins to drop on the lean side of best running.
start with engine running a little rich and then adjust towards lean &#40; turning screws in&#41;. after you get it set dont mess with the idle adjustment as to have to readjust. Also, adjust both screws equally. don&#39;t have one turned in 2 times and the other 1/2 for example. If you turn one a little, turn the other the same amount. I hope this helps you any. I worked good for me.. I have the same engine..

"Hi Mark, I have an 87 1750SS

"Hi Mark, I have an 87 1750SS with a Ford 2.3L and Cobra outdrive, so i&#39;m guessing we have pretty much the same boat.
My operators manual says...
Changes in fuel, altitude and climate may make it necessary to adjust the idle speed and idle mixture to obtain smooth engine operation. Before attempting to adjust carburetor, ensure the backfire flame arrestor is free of debris, dirt or grease.

&#40;Note&#41; Carburetor idle speed and mixture adjustment should not be attempted until engine is warm and it is known that ignition system &#40;inc spark plugs &#41; are to specifications. Any attempt to alter the carb to compensate for faulty conditions elsewhere will result in reduced fuel economy and overall performance.

With someone at the controls and the engine warmed up, run engine in forward gear and adjust the carb idle screw to obtain specified rpm &#40;600-650 in forward gear&#41; Turn the idle mixture needles, one at a time, in or out, until engine runs smoothly. Ensure specified rpm idle speed after readjusting idle mixture needles. Final adjustment should be with the idle mixture needles.

If your engine still fails to operate smoothly, or if the specified rpm idle cannot be attained, see you OMC dealer for further adjustment.

&#40;Note&#41; Do not attempt to increase idle speed except by the above procedure. Excessive idle speeds may result, causing damage to the gearcase during gear shifting maneuvers.

This is taken directly from my operator manual, for information, the idle mixture needles are the two screws at the bottom on the side of the carb, one for each barrel. The idle stop screw is the one that screws against the throttle linkage.